It appears that the lower gvw trucks with 4.8/5.3 use the pcm to control the heater for the 02 sensor more actively than the higher gvw 6.0 trucks. I am doing a swap vehicle and put a 6.0 file into the truck. With the headers the 02 sensors take forever to heat up and cycle. I tried a few different files from different models with the same results. When I put a 4.8 file back in the sensors heat up and cycle right away. Wiring from what I can see is identical. Anyone else noticed this? Anyone know where these parameters are located and how I might turn them on in a 6.0 file?